[x264-devel] [PATCH 6/6] checkasm: aarch64: Add filler args to make sure all parameters are passed on the stack

[Janne Grunau]

On 2016-11-14 23:54:53 +0200, Martin Storsjö wrote:
> This, combined with clobbering the stack space prior to the call,
> increases the chances of finding cases where 32 bit parameters
> are erroneously treated as 64 bit.
> ---
>  tools/checkasm-aarch64.S | 15 ++++++---------
>  tools/checkasm.c         |  2 +-
>  2 files changed, 7 insertions(+), 10 deletions(-)
> 
> diff --git a/tools/checkasm-aarch64.S b/tools/checkasm-aarch64.S
> index 1eb4546..7f66ead 100644
> --- a/tools/checkasm-aarch64.S
> +++ b/tools/checkasm-aarch64.S
> @@ -99,21 +99,18 @@ function x264_checkasm_call, export=1
>  
>      sub         sp,  sp,  #ARG_STACK
>  .equ pos, 0
> -// first two stacked args are copied to x6, x7
>  .rept MAX_ARGS-8
> -    ldr         x9, [x29, #16 + 16 + pos]
> +    // Skip the first 8 args, that are loaded into registers
> +    ldr         x9, [x29, #16 + 8*8 + pos]
>      str         x9, [sp, #pos]
>  .equ pos, pos + 8
>  .endr
>  
>      mov         x12, x0
> -    mov         x0,  x2
> -    mov         x1,  x3
> -    mov         x2,  x4
> -    mov         x3,  x5
> -    mov         x4,  x6
> -    mov         x5,  x7
> -    ldp         x6,  x7,  [x29, #16]
> +    ldp         x0,  x1,  [x29, #16]
> +    ldp         x2,  x3,  [x29, #32]
> +    ldp         x4,  x5,  [x29, #48]
> +    ldp         x6,  x7,  [x29, #64]
>      blr         x12
>      add         sp,  sp,  #ARG_STACK
>      ldr         x2,  [sp]
> diff --git a/tools/checkasm.c b/tools/checkasm.c
> index e10665c..8e3a928 100644
> --- a/tools/checkasm.c
> +++ b/tools/checkasm.c
> @@ -263,7 +263,7 @@ void x264_checkasm_stack_clobber( uint64_t clobber, ... );
>  #define call_a1(func,...) ({ \
>      uint64_t r = (rand() & 0xffff) * 0x0001000100010001ULL; \
>      x264_checkasm_stack_clobber( r,r,r,r,r,r,r,r,r,r,r,r,r,r,r,r,r,r,r,r,r,r,r ); /* max_args+8 */ \
> -    x264_checkasm_call(( intptr_t(*)())func, &ok, __VA_ARGS__ ); })
> +    x264_checkasm_call(( intptr_t(*)())func, &ok, 0, 0, 0, 0, 0, 0, __VA_ARGS__ ); })
>  #elif ARCH_AARCH64 && !defined(__APPLE__)
>  #elif ARCH_X86 || ARCH_ARM
>  #define call_a1(func,...) x264_checkasm_call( (intptr_t(*)())func, &ok, __VA_ARGS__ )

ok

Janne